Class 1 Assignment - CARTO Orientation + Feature Symbolization

Concepts & Themes:

This week’s assignment will encompass the following concepts, some of which will be previewed during the Class 1 lecture orientation:

• CARTO Signup
• CARTO Interface
• Uploading spatial data to CARTO (geodata)
• Feature symbolization with CARTO

General Course Orientation:

• Agenda

• Lecture 1

• Assignment 1 (This Document)

• Lecture Demonstration

• Course Introduction

• Course Expectations

• Course Syllabus

• CARTO Signup + Orientation:

To start, you will need to create your CARTO account that will be used for the duration of the course. While CARTO has several packages available for signup, we will be using the New School University account. You can find out about the CARTO student pack Here, which is different from the CARTO account you will use for this course. This secondary package requires a valid university email address. If you choose to use this option in the future, we will first need to delete your student account used in this course. In other words, you cannot use the same university email address for two separate CARTO accounts. To follow here, you will utilize your university email account to enact your first CARTO account within the New School University account:

• TNS CARTO login

• https://thenewschool.carto.com/signup

The New School CARTO platform Signup

If you have any particular problems during your signup, you can query at the Slack #technical-qa channel. Alternatively, you can email the Admin at the University Account:

• TNS CARTO ADMIN EMAIL

Acquire Data - Natural Earth:

• Once you have your account established, you will need to acquire a dataset for assignment 1. In this assignment guide, we will use Populated Places - less columns, simple version 36.51kb. as the example. You should choose another vector feature at Natural Earth for your actual assignment. Conversely, you can create your own data at geojson.io; or you can choose a completely different dataset.

Note: for weekly assignments that require a data upload to CARTO, keep in mind that your account has a size limit, typically 100mb. You will want to keep an eye on your upload sizes. For this first assignment, anything with a total upload size of <1mb is ideal.

• Navigate to Natural Earth Data.

• https://www.naturalearthdata.com/downloads/

• Keep in mind there are 3 scales of data available at Natural Earth. Generally the smallest scale will feature the smallest file sizes:

- To follow is the test dataset we will use for this assignment guide:

Populated Places - less columns, simple version 36.51kb.

Note: this is the same dataset that is used in the CARTO Guide - Getting Started with CARTO Builder.

• Download the data as .shp format to your local drive. Use QGIS to open the .shp. Once open, review the attribute table and note the Population and Rank columns. Either of these columns can be used for the symbolization component of this assignment:

Zip folder contains .shp for populated places.

## Prepare and Upload Data to CARTO:

• After review of the feature’s attribute table, export this feature to the .geojson format. While .shp can be uploaded to CARTO, it must be zipped correctly. Keep in mind that CARTO recognizes two default CRS - EPSG:4326 and EPSG:3857. Any data at Natural Earth will work as default EPSG:4326, and this CRS will be expressed in the .geojson format for the data.

geojson file format for the Natural Earth data.

• At this juncture, review the CARTO Guide - Getting Started with CARTO Builder. This guide will show the process of signup and initial dataset and mapping organization. To follow is the .geojson data uploaded to CARTO:

sucessful upload to CARTO

Note:if the upload fails, refresh the browser and wait a few minutes. Typically this will clear any ‘unknown’ upload errors.

Note: CARTO will add several new columns to the upload dataset. These new columns are discussed in the CARTO Guide - Importing API V1. This guide is very useful to understand the CARTO upload process generally.

Symbolize Data within CARTO:

• For this first assignment, the goal is to create a valid, stylized interactive map from the one dataset uploaded to CARTO. In the example dataset, thematically the population and integer rank for populations make most sense. In the first, proportional symbols for population size would work well; for the integer rank, either proportional symbols could work, or a categorical approach with different colors for different ranks. For your own assignment data, make sure to strategize your symbolization approach. The - Using ‘Style by Value’ with Point Geometries is very helpful here. Alternatively, the guide Aggregation Styles for Point Geometries is another approach that can be used for this assignment.

• Click the Create Map icon, lower-right of the dataset interface:

Click Create Map icon, lower-right

• Once complete, your dataset should be visualized into the maps interface:

Map instance prior to symbolization

• Navigate to the dataset layer itself, which allows for styling within the Style section:

Styling tab within the dataset layer

• Continue to style the data. Here as an example the styling consists of a size range based on the population maximum column; and as custom fill and stroke color choice. Under the Legend section, a simple legend has also been created. There are two options for the legend for these particular points features - by color, then by size:

Proportionally styling the points features

Simple Legend Creation for Cities within the Populated Places dataset based on color

Simple Legend Creation for Cities within the Populated Places dataset based on size

• Either before styling the data, or after, consider choosing an appropriate basemap to best correspond with your data styling approach:

Basemap Options with CARTO

Publishing the map within CARTO:

• To publish the map product, CARTO offers a series of options. Typically in this course, we will be utilizing a programmatic approach to develop weekly maps and the final project. But for now - early in the course - we will utilize the map publication features within CARTO to produce mapping results.

• To start, make sure to Toggle the ‘private’ tab to ‘Public - with Link’:

Public - with Link

• Next, click the Publish link and make sure to toggle off the ‘share with colleagues’ tab and onto the ‘Publish’ tab:

Publish Tab

• This will produce two results - a share link and also embed code for the map. For this assignment, copy the share link and paste into your short write-up described in the next section:

Share Link

Assignment 1 deliverable - CARTO Published Map:

• Once your mapping process is complete and you have secured and copied the share link, next create a short synopsis write-up of your assignment 1 map. Discuss the data; where the data originates; what’s important thematically about the data; what was your approach to symbolization of the data. This short write-up can include an image(s) if you wish, but the share link is the ‘proof of work’ requirement. Make sure the share link works as expected, i.e. test it out before inserting into your write-up. Upload the write-up with the map share link to CANVAS for assignment 1 as either a .txt or .pdf document.

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Resources:

• Getting Started with CARTO Builder

• Using ‘Style by Value’ with Point Geometries

• Aggregation Styles for Point Geometries

• CARTO Guide - Importing API V1

• Natural Earth Data

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